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v3.19.1

Regulatory Assets and Liabilities (Emera Maine) (Details) $ in Millions, $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 CAD ($) Customers km | Dec. 31, 2018 USD ($) | Dec. 31, 2017 CAD ($) | Dec. 31, 2018 USD ($) Customers km | Sep. 01, 2017 Customers
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Regulatory Assets |  | $ 1,569 |  | $ 1,411 |  |
Income tax expense (recovery) |  | $ (69) |  | $ (520) |  |
Bangor Hydro District [Member] | Federal Energy Regulatory Commission (FERC) [Member] | Electric Transmission [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  |  |  | 10.57% |  |
Bangor Hydro District [Member] | Minimum [Member] | Federal Energy Regulatory Commission (FERC) [Member] | ISO-New England (ISO-NE) [Member] | Electric Transmission [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  |  |  | 11.07% |  |
Bangor Hydro District [Member] | Maximum [Member] | Federal Energy Regulatory Commission (FERC) [Member] | ISO-New England (ISO-NE) [Member] | Electric Transmission [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  |  |  | 11.74% |  |
Maine Public Service District [Member] | Maine Public Utilities Commission (MPUC) [Member] | Electric Distribution [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Rate Increase (Decrease), Percentage |  | 5.30% | 5.30% |  |  |
Public Utilities, Approved Return on Equity, Percentage |  | 9.35% | 9.35% | 9.00% |  |
Public Utilities, Approved Equity Capital Structure, Percentage |  | 49.00% | 49.00% | 49.00% |  |
Maine Public Service District [Member] | Federal Energy Regulatory Commission (FERC) [Member] | Electric Transmission [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  | 9.60% | 9.60% | 9.60% |  |
Barbados Light & Power Company Limited [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  | 10.00% | 10.00% | 10.00% |  |
Income tax expense (recovery) |  |  | $ 9.6 |  |  |
Deferred Tax Liabilities, Regulatory Assets |  |  |  |  | $ 6.9 |
Dominica Electricity Services Ltd. [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  | 15.00% | 15.00% | 15.00% |  |
Number of Customers | Customers |  | 26,000 |  |  | 26,000 | 36,000
Grand Bahama Power Company Limited [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage |  | 8.50% | 8.50% | 8.80% |  |
Grand Bahama Power Company Limited [Member] | Scenario, Forecast [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Public Utilities, Approved Return on Equity, Percentage | 8.44% |  |  |  |  |
Brunswick Pipeline [Member] |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |
Length Of Pipeline | km |  | 145 |  |  | 145 |

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